Package of bags

ABSTRACT

THIS INVENTION IS DIRECTED TO A CHAIN OF IMBRICATED BAGS CONNECTED TOGETHER AND SUPPORTED BY TWO STRANDS OF TAPE, THE BAGS EACH HAVE TWO OVERLYING SIDES, ONE OF THE SIDES BEING SECURED TO BOTH OF SAID TAPES, THE BAGS OPEN ENDS ARE ORIENTED IN THE SAME DIRECTION RESPECTING THE TAPES AND EACH BAG AFTER THE BOTTOM BAG RELATIVE TO THE TAPE IS OFFSET ALONG THE TAPES AND OVERLIES THE OPENING OF THE UNDERLYING BAG, THE TAPES ARE SPACED APART ABOUT AN EQUAL DISTANCE WHERE THEY ENGAGE EACH OF SAID BAGS, AND THE LEAD BAG INFLATES TO A RELATIVELY SQUARE OPENING WHEN THE TAPES ARE HELD IN PARALLEL SPACED APART DISPOSITION ON A FLAT SURFACE, THE BAGS ARE SECURED TO THE TAPE WITH A TACK SUFFICIENT TOM ALLOW A PULL IN EXCESS OF 2 POUNDS TO SEPARATE THE BAGS FROM THE TAPE AND TO HOLD THE BAGS SECURELY TO THE TAPE AGAINST A PULL OF LESS THAN ONE-HALF POUND WHEN THE PULL IS APPLIED AT AN ANGLE OF 30*.

United States Patent {72] Inventor Ralph L- Wlng 3,161,347 12/1964 Hannon .i 229/69 Greenville,S.C. 3,285,405 11/1966 Wanderer 206/56(A) E fip 25 5 1967 FOREIGN PATENTS l e p Patented June 28.1971 215,455 1/1958 Australia 206/59(C) [731 -Assignee W. R. Grace Br Co. Primary Examiner-William T Dixson, Jr.

Duncan, SC. Atl0rneysJohn J. Toney, William D. Lee, Jr. and Edward J. Hanson, Jr.

[54] l zifa iii D fw i n g F igs. ABSTRACT: This invention is directed to a chain of imbricated bags connected together and supported by two [521 (1.5. CI 206/57, Strands fl e; h b h have two overlying sides, one of 229/69 the sides being secured to both of said tapes, the bags open [51] lnt.Cl B65d 75/42 ends are oriented in the Same direction respecting the tapes 1 Field of Search 206/57, 57 and each bag after the bottom bag relative to the tape is offset (Ali 56 (Alt 56 (DF 59 (C l; 229/69' 14 (Bi )1 along the tapes and overlies the opening ofthe underlying bag; 54''53 the tapes are spaced apart about an equal distance where they engage each of said ba s; and the lead ba inflates to a rela- [56] References Cited tively square opening when the tapes ar e held in parallel UNITED STATES PATENTS spaced apart disposition on a flat surface; the bags are secured 1,185,538 5/1916 Rand, Jr. 206/56(A) to the tape with a tack sufficient to allow a pull in excess of 2 2,653,752 9/1953 Vogt 229/69 pounds to separate the bags from the tape and to hold the bags 2,664,358 12/1953 Eichler.. 229/14(B.l.) securely to the tape against a pull of less than one-half pound 2,790,591 4/1957 Rosen 206/57(A) when the pull is applied at an angle of 30.

PATENTEDJ N 8,587,843 SHEET 1 0F 3 u M 7 {g 442a 3 1 29 2W3! V '30. 3-13! t V 12:; 7 JV FIG. 5 FIG. 4

FIG. 6

Inventor Ralph L. Wing byf hAH.

PATENTED JLIN28 l97l 3587.843

sum 2 [IF 3 FIG. 2

Inventor Ralph L. Wing PATENTED M28 1911 35 71343 sum 3 0r 3 FIG. 3

Inventor Ral h L. Wing PACKAGE OF BAGS The present invention relates to packaging and more particularly to a new and improved package of imbricated bags.

It is an object of this invention to provide a new and improved compact package of open ended bags that can be easily loaded from the front end of the package in continuous sequence from the same position without requiring a long reach to gain entrance to the lead bag or a long movement of the package to place the next bag in the leading position.

It is a still further object of this invention to provide a compact package of bags that will naturally inflate to a wide square type opening.

Another object of this invention is to provide a compact package of bags that will not disassemble readily by accident and yet separate readily when used in hand packaging operatrons.

A still further object of this invention is to provide a compact package of bags that can readily be directly joined to other similar packages of bags.

It is another object of this invention to provide such a compact package of bags that allows the top bag to be loaded while itself guarding the underlying bags against contaminatron.

It is a further object'of this invention to provide such a package that is economical.

In summary, carrying out my invention in one form thereof, a package of imbricated bags in provided with a plurality of identical bags secured to two parallel strands of tape by one side to both of the tapes. Each bag has one side secured to both of the tapes. The open end of each bag is oriented in the same direction respecting said tapes as all of the other bags and each bag after the bottom bag relative to the tape is offset along the tapes about three-fourths inch from the adjacent bag and overlying the opening of the underlying bag. The bags open to a relatively square opening when the tapes are held in parallel spaced apart disposition on a flat surface and they are inflated. The tapes are spaced inwardly from the sides of each bag about one-fourth the width of the bag within a tolerance of one-eighth the width of the bag. Each strand of tape has a tacky substance on one tape surface and the opposite tape surface is free oftack. The tensile strength of each tape is at least 25 pounds and preferably 55 pounds. The tacky substance has a tack strength when adhered to the bag sufficient to allow a pull in excess of 2 pounds to separate the bags from the tape and to hold the bags securely to said tape against a pull of less than onehalf pound when the pull is applied at an angle of 30 from the horizontal back across the chain of imbricated bags. Each of the bags is flattened with two overlying sides. The overlying sides of each bag are identically dimensioned, with a concave scalloped lip edge at the open end of the bag, the two scalloped lips of each bag overlying one another and they are evenly aligned. The invention is particularly useful with bags made from heat shrinkable plastic tubular film when the bottom closed end closure of the bag is formed by heat sealing. The polymers of vinyl chloride, such as saran are very desira ble plastic materials for this use. A slip agent or dust covering can be provided on the outer surface and inner surface of each of the bags to reduce the surface adhering properties thereof.

While the principles of the present invention are illustrated in the accompanying drawings and described in detail in the following specification, it is to be understood that the embodiment shown is by way ofexample only and that various modifications may be made without departing from the spirit of the invention.

FIG. 1 is a diagrammatic top plan view of one specie of the apparatus of our invention.

FIG. 2 is a diagrammatic perspective view of the support table and tape pulling unit of FIG. 3 with parts broken away to show the trigger mechanism and driving means.

FIG. 3 is a diagrammatic side plan view of the apparatus of FIG. 1 with the frame broken away.

FIG. 4 is a front view of a bag suitable for use of the apparatus.

FIG. 5 is a diagrammatic front plan view of a chain of imbricated bags mounted on tape suitable for use with the apparatus.

FIG. 6 is a diagrammatic side plan view of the chain of imbricated bags of FIG. 5.

FIG. 7 is a diagrammatic front end view of the support table and inflated bag of FIG. 3.

Referring now to the drawings and in particular to FIG. 1, a packaging apparatus 10 is shown therein embodying the invention in one preferred form thereof. The apparatus 10 has a frame 11 with an article inserting tray 12 reciprocally mounted thereon for reciprocation from the out position shown in solid lines in FIG. 3 to the inserted position 13 shown in dotted lines. A support table and tape pulling unit 15 is pivotally mounted on the frame. A forced air system 16 is mounted below the tray (as shown in FIG. 3 on the frame and directs air across the forward edge of the top of the support table and tape pulling unit as indicated by the arrows depicting the air flow path. A bag feed in arrangement 17 is provided at one end of the apparatus 10. A table dropping mechanism 20 is provided for pivoting the support table and tape pulling unit between operating and reloading positions.

The support table and tape pulling unit 15 is shown in particular detail in FIGS. 2 and 3. The unit 15 includes a support table 21 which has the shape of an isosceles triangle with the base side of the triangle oriented forward. The triangle tapers rearwardly and has a curved point 18 at its outer end so that it will not tear the bags. The forward edge 22 of the support table curves downwardly and has an opening 23 (FIG. 1) in the center of the curved forward edge cut. The unit 15 has a rectangular front plate 24 and a substantially rectangular bottom plate 25. The side plates 26 and 27 are substantially rectangular with their back edges curving and conforming to curved point 18 of the triangular support table 21. The side plates 26 and 27 are cut out along their rearmost bottom edges to expose the power means 28. A housing for the units power means 28 is formed by the members or walls 21, 24, 25, 26 and 27.

The power means 28 includes a power train which begins at the output end with a driven gear 30. A beveled shaft 31 having an end 31a secured to the gear 30 and extending from the gear 30 through a supporting bushing assembly 32 and through the gear housing 33 of clutch 34. The shaft 31 is connected to the gear housing 33 for joint rotation therewith. The

. clutch disc 35 of clutch 34 is secured to the bottom plate 25 by bracket 19 against rotation. The shaft 31 passes beyond clutch 34, through a second supporting bushing 36 and through a second clutch 37. The gear housing 38 of the second clutch 37 is connected to shaft 31 for rotation therewith. The clutch disc 39 of clutch 37 is connected by shaft 40 to an arm 41 which is connected by shaft 42 to a reciprocating rotary actuator or reversing air motor 43. Clutches 34 and 37 are override clutches of the type that have one direction drive and one direction slip. Both clutches drive when clockwise motion is supplied (as seen in FIG. 3) and are out of driving engagement when counter clockwise motion is supplied.

The reciprocating rotary actuator 43 is driven in a clockwise direction (as seen in FIG. 3) when the pressure is on line 44 which drives the driven wheel 30. Clutch 37 is engaged with driving shaft 31 and clutch 32 is disengaged allowing shaft 31 to rotate freely. When pressure is applied to the reciprocating rotary actuator by line 45 the rotary actuator has a counterclockwise motion and clutch 37 disengages allowing the driven disc 39 to slip and clutch 34 engages preventing the shaft 31 from reversing its motion. Drive gear 30 thus remains in locked position and will not turn counterclockwise.

Rotary actuator 43 is controlled by a valve 46 which is a two-way valve that switches the air from line 44 to line 45 and back to line 44 in response to its actuation by a pilot valve 47. Pilot valve 47 is an on-off valve operated through a spring loaded actuator 50 by a leaf spring trigger 51 which closes the pilot valve cutting off the air to the actuator in valve 46 which also has an internal spring loaded actuator. The pilot valve 47 is connected to valve 46 by line 52. A constant supply of air is supplied to valve 46 and to valve 47 via line 53, branch 54 extending to valve 46 and branch 55 extending to valve 47. The leaf spring trigger 51 extends through the support table 21 via slot 23 (FIG 1).

A meshing idler gear 56 can be intermeshed or released from meshing engagement with the drives gear 30 by manipulating the toggle lock 57.

Gear 56 is journaled in bracket 58 which is connected by rod 60 to the pivotal linkage 61 which moves the wheel in and out in response to the pivoting of handle 62. When the handle is in the position shown in FIG. 2 the toggle 57 is in the locked position and the meshing gears are in meshed engagement. When the handle 62 is lowered the two-position idler gear 56 is moved to its outward position.

Two freely rotating guide and orientation wheels 63 and 64 project from and are journaled in plate 24. Wheels 63 and 64 guide the tape that supports the bags down over the curved edge 22 of the support table and provides a twist in the tape so that it may be received between the meshing gears 30 and 56. The surfaces of the wheels 63 and 64 are knurled. The wheels are parallel to one another and laterally adjustably in slots 65 and 66 respectively. Screws 70 and 71 serve to tighten the inner shaft of the wheels in fixed position in the slots in any selected position along the slots.

Looking now at FIGS. 1 and 3, the guide mechanism 17 may be seen to include a series of horizontal, and spaced apart parallel and aligned guide rollers 73, 74, 75 and 76 which are rotatably mounted between the frame members 80 and 81; the topmost surface of each roller is substantially aligned with the upper plane of the supporting table 21. The rollers preferably have plastic or rubber surfaces so that they will not develop sharp ridges or bumps when scared or damaged. Such sharp projections could damage the bags, particularly when the ap paratus is used with plastic bags such as saran or polypropylene bags.

Several spaced apart rollers are provided so that the apparatus will be readily adaptable for use with bags of varying sizes. The rollers are spaced outward from the back of the sup port table 21 a distance sufficient to provide for a substantially complete straightening out of the bag by the time the bag reaches the forward edge of the support table in its loading position. This is important in providing for the easy inflation of the bag, for if the bag is folded down at its rear portion for a substantial distance when it is being inflated the air rnust usually be supplied with greater force to unfold the bag and lift it upwardly from the folded down region. This could result in the outer extremity of the bag remaining uninflated in some instances which would normally be undesirable. While the rollers can be lined up beyond the distance required to straighten out the bags this only makes the machine unnecessarily long. The chain of bags can also be fed over a roller more distant from the loading position than that necessary to straighten out the lead bags but then it is more trouble to unload to a chain of bags from the machine to switch bag sizes because the bags must be folded back into the supply box to prevent tangling. If the entire chain of bags is to be used up without directly attaching a subsequent chain onto its end it is desirable to have the bags pulled up and over the roller closest to the support table, commensurate with obtaining the needed bag straightening, to obtain the additional drag on the chain provided by the weight of the bags hanging down from the roller as long as possible for proper'tensioning and straightening of the bags and tape.

The rollers 73, 74, 75 and 76 are spaced sufficiently close together so that the chain of imbricated bags will not sag appreciatively down between the rollers when being fed across several of them. A very satisfactory spacing between the rollers has been found to be from about 2% inches to 3 inches using bags that are from l inches wide and 24 inches long and weigh 0.08 pounds to 18 inches wide and 32 inches long and weigh 0.13 pounds each when the bags are spaced threefourths inch apart with a tolerance of one-fourth inch.

It is important to provide the triangular support table shape over which the chain of imbricated bags can be drawn as they pass from the rollers because when the tapes are spaced inwardly one-fourth the width of the bag from each side, the forward corners of the bags fall down as shown at one side in FIG. 5 for purposes of illustration. This occurs as the bags are drawn up onto the table because the edges of the bags that extend out beyond the bags are not supported by the tapes and if the bags are supple, such as l.5 mils saran film bags, the corners fall down as the bags are pulled from the box up onto the apparatus. The tips of the triangle over which the bags first proceed is narrower than the spacing of the top so that the bags pass on to the support table where they are supported and held straight by the tape. The edges of the bags fall over the edges of the support table. As the bags are pulled farther up on the widening triangle the edges of the bags are continuously straightened or cammed outwardly by the wedge shape of the triangle. At its forward edge the triangle is wider than the bags and they are held straightened out.

The table positioning mechanism 20 pivots the support table and tape pulling unit 15 about the pair of trunnions which are connected to the frame 11. Only one of the trunnions 82 is shown in FIG. 3. The trunnions are secured in brackets 83 as seen in FIG. 3. The brackets are secured to the frame 11.

The unit 15 is raised and lowered by a single air cylinder 84 which is operated by a valve 85. The valve 85 is opened and closed by lever 86. A constant supply of air is supplied by line 87 to the valve 85 and when the lever is in the position shown in solid lines air is supplied to the cylinder 84 through line 88 and the piston (not shown) is driven forward pulling the table into its closed operable position. By moving the lever 86 to the position shown in broken lines the air to the cylinder 84 which has been holding the table closed is shut off and line 89 is opened allowing the air in the cylinder to escape slowly through a restricted orifice (not shown) allowing the unit 15 to open slowly. The air pressure to the cylinder is 30 p.s.i. and this provides a safety feature because an operator can manually overcome the closing pressure by pushing against the unit. This air pressure is also insufficient to crush a hand. The cylinder 84 may be seen to be connected to the frame by bracket 90 and to the unit 15 by bracket 91 through the pistons rod 92.

The reciprocating table 12 may be seen in FIGS. 1 and 3 to include sleeves and 101 which are slidably mounted on the supporting guide rods 102 and 103. The reciprocating tray has sides 104 and 105. Spring arms 106 and 107 extend from the sides 104 and respectively and converge inwardly.

The air blower unit 16 has a centrifugal air blower or fan inside casing 110 operated by an electric motor (not shown) positioned inside of the air blowers casing on the far side in FIG. 3. The air blower takes air in through the inlet 11 and propels it out through the outlet 112 into a chute 113 which has a sloping bottom wall 114 and sidewalls 115 and 116 (see FIG. 1). The chute 113 directs the air upwardly across the front or forward edge 22 of the support table 21 as indicated by the arrows in FIG. 3. A gate 117 closes the inlet 111 to the fan and thus prevent the movement of air through the fan and thence out exit 112 and chute 113. The gate is a flat disc that engages around the rim of opening 111. The cylinder 120 opens and closes the gate 117. Piston rod 121 connects the cylinder to the gate 117. The cylinder 120 is connected to the frame 11 by mounting bracket 120a. The piston in the cylinder 120 is spring loaded.

The piston is driven by air supplied by line 122 to close the gate 117 and when the air pressure is released the spring (not shown) opens the gate 117. Valve 123 controls the supply of air to cylinder 120 through the actuator and release of spring loaded lever 124. The gate valve, 117, is normally held open by the spring in cylinder 120 so that air is supplied from the blowers outlet 112 through the chute 113 across the front or forward edge of the support table 21. However, when the tray 12 is moved inwardly the beveled camming surface of sleeve 101 cams the lever 124 down admitting air to line 122 which drives the piston in the cylinder 120 outwardly moving the gate 117 across the inlet 111 shutting off the air entering the fan. When the tray 12 is retracted the lever 124 is released by the camming surface 125 shutting off the air to line 122 and opening the line so that the air in the cylinder may escape allowing the spring to drive the piston back in the cylinder opening gate 117 and admitting air once again into the fan so that it may be propelled from the fan's outlet 112.

A plurality of imbricated bags that are arranged along the two strips of adhesive tape 128 and 129 may also be seen in FIGS. 1, 3, 4,5, 6 and 7. In FIG. 3 one bag 131 is shown inflated on the support table 21. The chain of imbricated bags 130 may be seen to be made up of numerous individual bags 131, 132, 133 and 134, in FIG. 6, for example. These bags are adhered to the two parallel and spaced apart tacky tapes. The two may be seen in FIGS. 1 and 7 in operating engagement on the machine, pulled down over the forward edge 22 of the support table 21 and passed around the knurled wheels 63 and 64 (as may also be seen from FIGS. 2 and 3) and between the meshing gears and 56. The imbricated bags extend back across rollers 73 and 74 that support them. The bags extend over roller 74 and down into a stock box 143. Rollers 75 and 76 are provided for use in supporting longer bags. The bags should usually be at least substantially horizontal before they are inflated. The chain of bags or package 130 is hooked to a separate chain of bags or package 145 which is in another stock container 146. The two chains of bags are joined by securing the end portions of the tapes 128 and 129 and the beginning portions of tapes 147 and 148 in the fresh box 149 of imbricated bags.

The tapes 128 and 129 are spaced apart on the imbricated bags about one-fourth the width of the bag in from each side within a tolerance of one-eighth the width of the bag so that the bags may open into a wide oval opening. The opening approaches a circular configuration of the somewhat square configuration of FIG. 7.'The tapes are spaced inwardly from their respective sides about an equal distance. The tolerance for the equal inward spacing is about one-half inch if the bags are to be optimally pulled into the loading position with the opened end evenly aligned. Thus in the example shown in FIGS. 4, 5 and 6, the bag is 12 inches wide the TAPES are 5% inches from inside edge to inside edge, the tapes are three-fourths inch wide, the distance from the outside edge of each tape to the nearest side edge of the bag is 3 inches. The bags are offset from one another along the tape three-fourths inch. The tape contact surface is IVs square inches on each bag, 9/l6-square inch contact surface per tape. Depending on the size bag used the tape contact surface per tape may desirably vary from onefourth to l square inch per tape. The tack strength should be such that from 2-4 pounds, more preferably about 2 pounds, will separate the bag from the tapes and 1% pound, more preferably l pound, will not separate the bag from the tapes when the pull is provided on an angle of 30 in the direction toward which the bags are normally stripped from the tapes. If a high tack tape is used the width of tape and the area of contact can be substantially reduced by several fold. The tensile strength of the tape should, however, be maintained above about 25 to 55 pounds per tape; more preferably 55 pounds per tape. In order that the tapes not cause the lead bag to trough or curve side edge to side edge when being positioned in the loading position the tape extends 18 inches beyond the lead bag in the chain.

If the surfaces of the bags tend to adhere together a dusting of tale to cover the surfaces of the bags inside and out may be used to overcome the sticking together of the surfaces.

By an aspect of our invention in a preferred form thereof, a process is provided for sequentially loading a chain of imbricated bags supported by two parallel spaced apart tapes each of which has one tacky surface engaging one side of each bag. The other side of the tape is not tacky and faces outwardly. The two spaced apart tapes are pulled from a medial position between their normal spaced apart paths and at the same time their respective tacky surfaces are squeezed together by gripping the tapes between the teeth of a pair of gears and sequentially activating the gears to pull the tape in step wise fashion. The tape accumulates below the gears and can be periodically removed by severing the tape below the gears or by waiting until a run of bags is completed. Because the respective tacky surfaces have been squeezed together the tape is not a problem from the standpoint of sticking to everything and forming a mass and fouling the efficient operation of the apparatus.

By pulling the tapes from a medial position between their normal spaced apart paths the chain of imbricated bags is moved in a straight line without any substantial problem with canting from side to side and without a requirement for constantly adjusting the pull so that the chain will move in a straight line to the loading position. Each bag is pulled into the loading position in almost exactly the same position as the previous bag to facilitate easy opening and loading without providing compensation for irregularity in the bag's position.

It is preferable that the tapes be pulled from a position below the plane of the bags when they are in the loading position. It is also desirable for the tapes and bags to pass through the loading position in an even horizontal plane with the very front edge of the bags being slightly pulled down over a rounded edge. The tapes should preferably be maintained spaced apart as they pass through the loading position and the plane of the tape should be changed fairly abruptly desirably by engaging the tapes around idler wheels spaced apart about the normal distance of the tapes spacing. By positioning the tape receiving surfaces of the idler wheels both perpendicular and at right angles to the tapes original horizontal plane of movement, the orientation of the tape can be correspondingly changed.

The bags are moved into the loading position sequentially, only the topmost bag being fully in the loading position. The upwardly oriented side of this topmost bag is free of attachment so that it may be readily opened. The bottom of the chain of imbricated bags is not tacky and slides easily in response to the pulling force applied to the tape. The bottom side of the forwardmost bag in the imbricated chain is firmly supported so that an item placed in the bag will not cause the entire bag to fall or otherwise deform until the bag is removed from the loading position.

The bags are sequentially inflated as they are positioned in the loading position by initially reducing the air pressure above the unattached side of the bags to partially open the bag and subsequently directing a stream of air into the partially open bag to increase the pressure inside of the bag and thereby fully open the bag. An article is loaded into a reciprocating tray and this reciprocating tray is moved forward shutting off the stream of air to the inside of the bag and the tray moves on into the bag before the bag can close and simultaneously peels the bag from the tapes starting at the bag's forward edge and proceeding toward the bottom of the bag until the bag is free from the tape. Simultaneously with this action the article is pushed from the tray into the bag and thereafter the loaded bag is disengaged from the tray and the tray is drawn back out of the way for reloading.

By peeling the bag from the tape much less force is required than if the bag is stripped from the tape in a direct plane. This is because the bag is gradually stripped from the tape by pulling upwardly against the bag starting at the edge of the top lip and pulling the bag from and lifting the bag backward away from the tape until it is free.

The bag may be separated from the tape in the manner described by employing spaced apart spring arms on the tray having reduced dimensions for first entering the bag and increasingly spaced apart and upwardly increasing dimensions that engage the upper side of the bag as one tray progresses into the bag lifting the bag off of the tapes and pushing the bag back from the tape in the same motion in the manner of a moving wedge, see FIG. 3, the shape of arm 107. The article being bagged can be slipped through the tray between the spring arms simultaneously with the inward movement of the tray. The outward movement of the spring arms against the sides of the bag would also tend to hold the bag in position on the tray while the article is being loaded into the bag.

This process may advantageously be used to sequentially load a chain of imbricated bags with items such as cleaned and dressed turkeys or other market ready items.

To place the apparatus 10 of this invention in operation and operate it in a preferred manner, using l2-inch wide by 20- inch long bags and a preferred process of this invention, the support table and tape pulling unit is opened to the position shown in broken lines in FIG. 3 and the toggle lock 57 is open so that the gear 56 is spaced from gear 30. The knurled wheels 63 and 64 are adjusted apart equal distances from the center approximately the same spacing as the two lead tapes of the chain of bags. The knurled wheels need adjusting only if the width bag being used varies substantially. If adjustment is necessary the screws 70 and 71 are loosened and the respective wheels are correspondingly moved in or out and then the screws are tightened again. To feed the chain of bags 130 into the machine the two lead tapes 128 and 129 are manually raised out of a package containing a chain of imbricated bags and fed up and over an appropriate roller so that they lay over the roller as shown in FIG. 1. The chain of imbricated bags 130 can be seen to passbetween roller 74 and 75 and to lie across the top of the rollers 73 and 74.

The chain of bags 130 is manually pulled over above the support table 21. The tapes are drawn down over the forward edge of the table so that they engage the table with their nontacky surfaces. Then tape 128 is twisted one-half turn counterclockwise and its tacky surface is engaged over the knurled wheel 63 as shown in FIG. 7. Tape 129 is twisted one-half turn clockwise and its tacky surface is engaged over knurled wheel 64 as is also shown in FIG. 7. The ends of the two tapes are stuck together tacky surface to tacky surface and positioned or threaded between the gears 30 and 56 which are open. The locking toggle 57 is then pivoted to move the idler gear 56 into mesh with the driven gear 30 and then locked by pushing the toggle over center (FIG. 2). After the toggle is locked the tape is securely held crimped between the intermeshed gears.

After the chain of imbricated bags 130 has been positioned in the machine and the tape secured between the intermeshing gears 30 and 56, the lever 86 is manually moved to open valve 85 and supply air to cylinder 84 which drives the piston and piston rod 92 forward pulling the support table and tape pulling unit 15 up into its operating position shown in solid lines in FIGS. 1 and 3.

When the imbricated bags are being fed or loaded into the machine it is desirable to have the tray 12 sufficiently forward to engage the lever 124, and cut off the air from fan 110. This prevents the air from buffeting the forward edge of the bags and inflating them before the apparatus 10 is ready for sequential operation. Of course, the machine may be loaded with bags with its power both air and electric off. The air would ten be switched on before activating lever 86 to raise the unit 15. The fan 16 could be switched on subsequently if desired. Once the table and tape pulling unit 15 is in its operating position the driving wheel 30 would convey the tape forward until the lead bag in the chain 130 engages against the trigger 51 opening valve 47 (FIG. 2). The tray 12 is then retracted to its outer position for loading, switching the air on which inflates the lead bag.

When the tray is retracted the lever 124 is released by the cam surface 125. This closes valve 123 admitting air to cylinder 120 via line 122 and opens the gate 117 admitting air through inlet 11] into the fan which propels the air outwardly through outlet 112. The air is guided by the chute 113 across the forward edge of bag 131 and the air stream passing over the bag reduces the pressure over the bag and the air in the bag expands slightly, slightly lifting the bag. The air stream then catches inside the bag and further lifts the bag to fully open position. Some bags that have desirable properties such as very thin walls, clear see-through characteristics and a very flexible hand, such as saran bags, must be powdered inside to be fully operable. The powder prevents the sides of the bags from adhering together and excluding air from between the two inner walls of the bags which would make the opening of the bag very difficult using only the air system employed here. The powder may be a material such as cornstarch if edibles are to be placed in the bags.

Turning now to the sequential operation of the apparatus, an operator deposits an item to be packaged on the tray 12. The item may be supplied by any means such as, for example, a push cart or conveyor (not shown). The tray 12 is pushed forward by the operator. As the tray moves forward its conveying arms enter the mouth of the bag 131. After the arms have entered about one-fifth of the way into the bag the camming surface engages the lever 124 actuating the gate 117 to close off the air into the fan 110 and thereby shut off 7 the air from the fan. It is preferable to shut off the air because as the bottom edge of the tray 12 passes over the chute 113 it deflects the air downwardly against the mouth of bag 132 that underlies the bag 131 and tends to inflate the second bag before the first bag 131 is stripped from the tape. This tends to cause the bags to be partly stripped from the tape prematurely and it also tends to tear the bags.

As the upper shoulder portions of the arms 106 and 107 enter further into the bag they strip the bag from the tape by pulling upwardly on the upper lip of the bag as the tray is pushed further into the bag drawing the bag upwardly on the arms. The arms can be seen to get higher at their basejuncture with sides 104 and 105 as shown in FIG. 3. It may be seen that the forward edge of the bag at the lower lip has been pulled slightly down over the curved forward edge so that the increasing t'pward camming of the arms is excentuated by the downward curved position of the lower lip. This substantially assures that the lower lip of the bag will peel upwardly from the tape with the peeling progressing from the very front edge toward the rear. This greatly reduces the amount of force required to strip the bag from the tape. A much greater force would be needed to shear the bag from the tape in the plane of the tape. Even the force needed to directly pull the bag from the tape at one time straight away is very high.

As the bag is stripped from the tape the tray is progressing into the bag thus loading the bag. The article being loaded into the bag is shoved simultaneously as the tray approaches is fully in position out through the spring arms 106 and 107 opening the arms apart and spreading the bag further thus pulling some at the outside edge of the bags contact with the tape. The article is also simultaneously shoved from the tray and the bag is shoved from the loading position of the support table and, because ofits relatively slick surface, it slides easily across the other bags and onto a second station (not shown) which may be a conveyor or a table for moving it to a separate position for further processing such as closing by a person standing just beyond the bagging position. The rollers 72 and 73 aid in moving the bags out of the way to the next station for further processing so that another bag may be loaded. Alternatively if the tray does not have the upper camming shape to the arms 106 and 107, the operator may hold her arm tilted upwardly and engage the forward edge of the bag stripping it from the tape.

As the bag is stripped from the tape the trigger 51 is released by the lower lip of the bag. The trigger 51 moves inwardly due to its spring action engaging the spring loaded slide actuator 50 which closes the pilot valve 47 cutting off the air to line 52 which allows the air through line 54 to move the slide in the valve 46 to open line 44 and reverse the rotary actuator 43 driving gear 30 clockwise through the power train. The tape is thus conveyed through the meshing gears 30 and 56 a sufficient distance to pull the next bag 132 in the chain against the trigger 51 drawing the trigger forward away from the spring loaded actuator 50 which opens the pilot valve 46 admitting air through line 52 against the slide in the valve 47 which switches the air to line 45 reversing the reciprocating actuator to a counterclockwise rotation. This reverses the movement of the shaft 42 opening clutch 37 and breaking the power train. Clutch 34 engages so that the drive wheel 30 is locked and cannot reverse its motion. Thus the tapes 128 and 129 are held crimped between gears 30 and 56 and the bag 131 thus is secured in loading position.

The leaf spring trigger 51 because of its extra bending displacement provides some degree of override in response to the bags pressure against it insuring a complete disengagement of the trigger from the slide 50. The override is provided by the momentary delay in the reversal of the reciprocating rotary actuator. The override prevents the shattering type of switching of the power means that could otherwise occur due to a usually inherent slight giving and stretching of the forward lip of the plastic bags that would usually be used on the apparatus. The lip of the bag is engaged with and serves to actuate the trigger 51.

When the tape is pulled by the gears 30 and 56 its nontacky surface slides over the upper surface of the support table 21 and the curved edge 22. The tacky surfaces of the tape are engaged on the knurled surfaces of the wheels 63 and 64 causing the wheels to rotate as the tape is pulled. Because the wheels 63 and 64 are knurled the tape separates from the wheels in response to only very slight separating forces. This reduces the power requirements for machine operation.

As the tray is manually moved back to the loading position for reloading, lever l24 is released by the camming surface 125 thereby opening valve 123 releasing the air from the cylinder 120 allowing the spring in the cylinder to draw the piston into the cylinder opening up the inlet 111 to the fan 110. By the time the fan is open again, the loaded bag or package should have moved out of the way and the next bag is usually already in the loading position.

The fan 110 propels air through outlet 112 and the chute 113 directs the air against the forward edge of the bag where it initially proceeds on across the upper surface of the bag 131 until sufficient opening is attained in the bag for the air to fully enter the bag 13]. Once the bag is fully inflated and opened by the air, the apparatus is ready for the repetition of the procedure just described which can be sequentially continued indefinitely.

When the chain of bags in the package 143 is about to be exhausted a new package 146 containing a new chain of bags may be moved up adjacent to the package 143 as shown in FIG. 3 and the end tapes 128 and 129 from the chain of imbricated bags in package 143 may be attached to the lead out ends of tapes 147 and 148, respectively, by adhering the tapes together so that the new chain will be pulled onto the apparatus and fed'through the apparatus in the same manner as the chain 130. The tapes 147 and 148 must be attached so that the tacky tape sides are oriented up in the same manner as the chain of bags 130. It is obvious that this sequence can also be continued indefinitely as the trailing ends of tapes 147 and 148 may be attached to another package of bags and so on. Of course, once the package 143 is exhausted the empty package container may be removed and the package 149 may be slipped into its position.

To shut down operation it is only necessary to cut off the fan motor and the air compressor (not shown) if this is the source of air. This may be done at any time during the sequence of operation but probably it is most conveniently done at the time when tray 12 is in the outer position shown in FIG. 1.

It has been found to be preferable to power the machine with air with the exception of the fan because the air system does not normally present the other general electrical insulation, corrosion and deterioration problems presented by electrical wiring and devices under such rigorous operating conditions as meat packing plants where the apparatus is constantly wet down, washed and bufi'eted with water, steam and other cleansing mediums. Electrical apparatuses also present a safety hazard because of the possibility that personnel operating the machines will be shocked due to insulation failure under the wet operating conditions. The air powered machine usually provides for safe operation, lower maintenance costs and less expensive installation costs because there is a reduced need to protect electrical parts. It has been found that it is usually best to operate the fan with electrical power because of the high power requirements which necessitate the use of much higher air pressure than the 30 pound pressure which has been found sufficient to operate the apparatus when the fan is directly powered electrically. This split power means reduces the overall power requirements.

A reciprocating rotary actuator has been found to be the preferable driving means because it has low maintenance costs and low power requirements. In the embodiment shown a 150 inch pounds torque rotary actuator was used. The use of the air cylinder 84 to raise and lower the support table and tape pulling unit 21 has been found to be particularly desirable because the 30 pounds of pressure required to pivotally move the support table and tape pulling unit 15 which weighs about 30 pounds, in the embodiment shown, is not a sufficiently large force to present a safety hazard should someone get a hand or another body part in the way of the movement of the support table and tape pulling unit 15. The air cylinder which is a double acting type air cylinder when operated at about 30 pounds of air pressure provides sufficiently slow-medium motion in opening and closing the apparatus to not delay operation and yet to give the operator time to observe and correct any binding, such as the bags not moving upwardly over the roller as the tape moves forward which could cause a break in the tape due to overstretching should the bags for some reason be held by the package due to a package being incompletely opened or some such. This speed of opening and closing, requiring about 4 seconds, leaves the operators hands free to adjust the tape after he positions the handle 86 to actuate the cylinder 84.

When it is desired to switch the size of the bags or to change the tape for some other reason lever 86 is shifted to the position shown in dotted lines in FIG. 3 closing the air inlet to line 88 into the cylinder 84 and opening the outlet for the air from the cylinder via line 89 allowing the table to fall slowly backwards, the table being pulled backwards by its offcenter weight about the pivot 82 which is engaged in bracket 83 and their counterparts (not shown) on the other side of the unit 15. The toggle 57 is moved to move idler wheel 56 out of mesh with wheel 30 releasing the tape from engagement therebetween. The chain of imbricated bags can then be lifted back and fed back between rollers 74 and 75 into the package 143. The apparatus is then ready for loading with a chain of imbricated bags in the manner previously described. Of course, a chain of bags could be used up and the ends of the tape would simply run out between the meshing gears 30 and 56. For reloading, the unit 15 would still be dropped back and the toggle 57 opened.

lclaim:

l. A package of imbricated bags comprising two strands of tape, each of said strands of tape having a tensile strength of at least 25 pounds and a tacky surface and an opposite surface free of tack; a plurality of open ended bags, each of said bags having two overlying sides of substantially identical dimension, each of said bags having one side secured to said tacky surface of both of said tapes, the tacky surface of each of said tapes having a contact area of from about one-fourth to 1 square inch with each of said bags and said tacky surface having a tack strength when adhered to the bag sufficient to allow a pull in excess of 4 pounds to separate the bag from the tape and to hold the bag securely to said tape against a pull of less than one-half pound when the pull is applied at an angle of 30, the open end of each of said bags oriented in the same direction respecting said tapes as all of the other bags and each bag after the bottom bag relative to said tape ofi'set along said tapes and overlying the opening of the underlying bag; said tapes spaced apart about an equal distance where they engage each of said bags and inwardly from the sides of each bag about one-fourth the width of the bag within a tolerance of one-eighth the width of the bag; said bag opening to a relatively square opening when the tapes are held in parallel spaced apart disposition on a flat surface. 

